Today is the 224th birthday of Louis-Jacques-Mandé Daguerre, inventor and namesake of the first commercially viable photographic process, the daguerrotype. While the world’s first known photograph was taken by another Frenchman called Nicéphore Niépce - who later joined forces with Daguerre - it was Daguerre who perfected the process; which involved the creation of a direct positive image on a silvered copper plate through exposure, development and fixation. The French government subsequently acquired the rights from Daguerre in exchange for a lifetime pension, and went on to present the process as a gift to mankind on 19 August 1839. Today, Google is celebrating Daguerre’s birthday with a doodle featuring a stylised black-and-white family portrait.